The most basic optical fiber communication system consists of optical transmitters, optical receivers, optical fiber lines, repeaters and passive components. The optical transmitter is responsible for converting the signal into an optical signal suitable for transmission on the optical fiber, the optical fiber line is responsible for transmitting the signal, and the optical receiver is responsible for receiving the optical signal, extracting information from it, and then transforming it into an electrical signal, and finally obtaining the corresponding voice , Images, data and other information.
(1) Optical transmitter
Optical transmitter is an optical transceiver that realizes electro-optical conversion. It consists of a light source, a driver and a modulator. Its function is to modulate the light wave emitted by the light source from the electric signal from the electric terminal to become a modulated light wave, and then couple the modulated light signal to the optical fiber or cable for transmission.
(2) Optical receiver
Optical receiver is an optical transceiver that realizes optical/electrical conversion. The optical transceiver consists of an optical detector and an optical amplifier. Its function is to convert the optical signal transmitted by the optical fiber or optical cable into an electrical signal by the photodetector, and then restore it to the electrical signal before transmission after being processed by the amplifier.
(3) Optical fiber or cable
Optical fibers or cables constitute light transmission paths. Its function is to couple the dimmed signal from the sender to the light detector at the receiver after long-distance transmission via optical fiber or cable to complete the task of transmitting information.
(4) Repeater
The repeater consists of a light detector, a light source and a decision regeneration circuit. It has two functions: one is to compensate the attenuation of the optical signal when it is transmitted in the optical fiber; the other is to deal with the impulse of waveform distortion.
(5) Passive components such as optical fiber connectors and couplers
Since the length of the optical fiber or optical cable is limited by the optical fiber drawing process and the construction conditions of the optical cable, and the drawing length of the optical fiber is also limited (such as 1Km). Therefore, an optical fiber line may have the problem of connecting multiple optical fibers. Therefore, the connection between optical fibers and the connection and coupling between optical fibers and optical transceivers are indispensable for the use of passive components such as optical fiber connectors and couplers.
The principle of optical fiber communication is: at the transmitting end, the transmitted information (such as voice) must first be converted into electrical signals, and then modulated to the laser beam emitted by the laser, so that the intensity of the light changes with the amplitude (frequency) of the electrical signal. It is sent out through optical fiber; at the receiving end, the detector converts the optical signal into an electrical signal after receiving it, and then restores the original information after demodulation.
Tags : Fiber Optic Cable, Fiber Optic System
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